Wrestling is scripted, that is something that has been known for a long time now, but it seems that even though everything that happens in a WWE ring is planned out, there is always room for error and in front of a live audience, there are usually a number of accidents. Over the past few decades, there have been a number of injuries in a WWE ring that have cost superstars their careers, either because of the carelessness of the person they were in the ring with or by a cruel twist of fate that left them unable to be cleared by medical staff or physically unable to compete in a ring anymore.

WWE has changed a lot of rules in recent years so that their superstars are much safer in the ring. This includes taking out chair shots to the head and moves that the company feels could cause an injury. Many spots, moves and even objects have been removed from regular programming to try and limit the risk of an accident or injury from repeated use of these methods.

Despite this, there are still superstars that are being forced out of the squared circle all the time through injury, the following list looks at just 15 WWE star who was forced out of the ring because of the carelessness of the person that they were in the ring with.

15 Paige

Paige was once seen as the future of the Women's Division in WWE as a former NXT Women's and Divas Champion, but after a whirlwind year in her personal life, Paige finally got her career back on track in November 2017 and returned to WWE with a new attitude.

It was thought that the former Champion would finally be able to push her career forward.

That was until she was part of a multi-diva match at a WWE Live event that also included Sasha Banks. Paige had already undergone neck surgery merely a year before and it seems that The Boss delivered a kick to Paige that left her not only unable to finish the match but unable to then return to the ring. Paige recently announced her retirement from the ring and has since been made SmackDown Live General Manager.

14 Tyson Kidd

Tyson Kidd was one of the graduates from The Hart Family Dungeon and was on a decent run in WWE when he crossed paths with Samoa Joe back in June 2015. Joe delivered a Muscle Buster to Kidd as part of a dark match on Monday Night Raw and it seems that this move caused Kidd to suffer a life-threatening spinal injury.

Kidd hasn't wrestled for almost three years since the match following surgery on his neck and spine. He has since been announced that Kidd's in-ring career is over and he is now working as a producer backstage in WWE. His profile has been moved over to the alumni section of the WWE website which was confirmation that the former Tag Team Champion would not be returning to the ring.

13 AJ Lee

AJ Lee is a former Divas Champion and someone who was able to push forward women's wrestling throughout her career, but when she retired to the company back in 2015 many fans thought it was because of her husband CM Punk's issues with WWE when in fact AJ Lee revealed in her autobiography that it was due to her injuries that were piling up at that point.

AJ recalled that she suffered seven concussions in her career, the most memorable being in a match with Brie Bella back in 2013, as well as irreparable damage to her spine. The damage to her cervical spine was ultimately the biggest factor in her decision to end her eight-year career in the ring, but it wasn't one that she took lightly and this is one of the biggest reasons why AJ will never wrestle again.

12 Joey Mercury

Joey Mercury was once a Tag Team Champion alongside John Morrison when the duo was known as MNM alongside Melina, but it seems that this part of his career is something that Mercury would rather forget.

He was part of a fatal four-way match back in 2006 at Armageddon when The Hardyz set up a ladder in the corner of the ring and Jeff jumped into the bottom of the ladder and managed to propel it into Mercury's face, who was being held in place by Matt Hardy. This was the end of his tag team career and even though he has since found a level of fame alongside Jamie Noble and Seth Rollins and even as part of CM Punk's Straight Edge Society, Mercury has been best used backstage ever since.

11 Edge

Edge was one of the best heels in the history of WWE for a number of years before he was forced to retire from the company back in 2011. Edge's retirement seemingly came from out of nowhere, but it is thought that the straw that broke the camel's back was when Edge suffered a neck injury in his match with Alberto Del Rio.

Just days later Edge was forced to relinquish the World Championship and walk away from the wrestling business for good.

He was then inducted into the WWE Hall of Fame the following year and has since made a career for himself as an actor, knowing that if he ever made the decision to return to the ring and takes one bad bump, he could be left paralyzed.

10 Perro Aguayo Jr

Rey Mysterio will always be a legend to WWE fans all over the world, but after he decided to walk away from WWE back in 2015, Mysterio headed to AAA. It was while he was wrestling for AAA that Mysterio teamed with Extreme Tiger against Manik (TJ Perkins) and Perro Aguayo Jr.

This match saw Mysterio deliver a dropkick to Perro's shoulders which saw him thrown forward into the ropes with such force that it actually snapped his neck. The other three stars were unaware that Perro was hurt and continued the match before Perro was rushed to the hospital but he had passed at just 35 years old. Mysterio is currently in talks with WWE to return to the company after he made a shock return at the Royal Rumble back in January, which was said to have been a one-off appearance.

9 Bret Hart

Bret Hart was known as The Best There Is, The Best There Was and The Best There Ever Will Be throughout his time in the squared circle, but it seems that even Hart had his own fair share of issues when it comes to issues with co-workers. Aside from the obvious Montreal Screwjob, it seems that Hart's career actually came to an end at the hands of Goldberg. Back in 1999, Bret Hart faced Goldberg at Starrcade.

After taking a stiff kick to the head, Hart suffered a concussion that later led to him retiring from the business.

While Hart has returned to WWE in the years that have followed, it could be argued that he hasn't wrestled on the same level and hasn't been able to return as a full-time star since.

8 Stone Cold Steve Austin

Stone Cold Steve Austin is a WWE Hall of Famer and one of the main stars of WWE's Attitude Era, but it seems that even The Texas Rattlesnake's career came to an abrupt end back in 1997 when he faced Owen Hart at SummerSlam for the Intercontinental Championship.

Austin went for a piledriver and when Hart reversed it into one of his own, Austin's head wasn't in the correct place and he spiked the canvas causing severe injury to his neck. Austin revealed that he lost feeling in his limbs after this and even though he continued to wrestle for WWE following the injury and retired back in 2003, an incredible 6 years later it was this injury that always held him back and caused him a number of issues in the ring from that moment.

7 Sting

Sting was a legend in both WCW and TNA but there was always a shadow hanging over his career when it came to the fact that he had never performed for WWE. This all changed back in 2014 when Sting arrived in WWE at Survivor Series to cost The Authority their match and their jobs. Sting then went on to face Triple H in a losing effort at WrestleMania 31 and then Seth Rollins at Night of Champions for the World Championship.

It was as part of this match that Sting took a turnbuckle power bomb that went wrong.

It left the legend with a neck injury that ended his career. Sting revealed that he had retired from the wrestling business during his Hall of Fame induction ceremony the following year.

6 Droz

Droz came to WWE as a former NFL player and looked like someone who had a lot of potential in the squared circle. Droz was part of The Road Warriors for a point in his career, but it seems that much of this is forgotten because of the way Droz was forced to exit the business.

It was seemingly a freak accident in a match between Droz and D'Lo Brown back in October 1999 when Brown went for a powerbomb he slipped in the ring and Droz was left paralyzed. The star continued to work for WWE as a writer and columnist and has since regained the use of his arms and upper body which has allowed him to be part of a number of projects outside of the ring.

5 Chris Nowinski

Chris Nowinski is a name that many current fans will be unfamiliar with but he was a part of the first ever season of Tough Enough before the company decided to sign him to a contract with a number of other competitors who were part of the show.

Nowinski was given a decent gimmick and looked like someone who could go on to be a legitimate mid-card star, that was until the 2003 Royal Rumble. Nowinski was supposed to recieve a double dropkick from Rey Mysterio and Edge, but it seems that Edge botched his dropkick and actually landed on the star's face leaving him with a concussion. Ever the competitor, Nowinski tried to fight his injuries but was forced to succumb a few months later and leave the business. He hasn't wrestled since.

4 Corey Graves

This is a strange situation since Neville and Corey Graves were once NXT Tag Team Champions together, but after Graves turned heel on Neville and the duo started a feud against each other, Grave suffered a legitimate concussion. This was Graves first major injury and led to him being out of action for a number of months before he later returned and then suffered another concussion in a six-man tag match, which was when he decided to retire.

Graves has since been given the unique opportunity to work as a commentator for WWE on Monday Night Raw and SmackDown Live.

Unfortunately he can't work as an in-ring performer for WWE anymore because of the concussions that he suffered earlier in his career and during his time in NXT.

3 Rick Rude

While Sting could claim that Seth Rollins ended his wrestling career back in 2015, it seems that Sting played his own role in ending Rick Rude's career during his days in WCW, long before he ever made the decision to sign for WWE in 2014.

Sting and Rude were placed in a feud while they were both part of the WCW roster, a feud that many fans thought was one of the best in the company at the time and as part of a match between the duo Sting delivered a backdrop to Rude and he landed flat on his back on the entrance ramp. It seems that this injury was one of the main instigators in Rude's retirement not long afterward since the star was only part of a couple of matches after this one.

2 Jose Estrada Jr

Edge's career may have ended as a result of a number of injuries that mounted up over a number of years, but it seems that The Rated R Superstar himself managed to end the career of Jose Estrada Jr before it had ever begun back in 1998.

This was Edge's first-ever televised match for WWE and he performed a somersault to the outside where it seems that Jose's neck was legitimately injured when he caught him. The match ended via cutout after it was revealed that Jose had suffered a broken neck and that was essentially the end of his career. Estrada had been part of WWE for almost a year when this happened and hasn't been able to wrestle over the past two decades because of the injury he suffered at the hands of Edge.

1 CM Punk

CM Punk is one of the best-known wrestlers in the world right now even though he left the company back in 2014 and has since moved on to a career in UFC. Punk remained quiet about his reasons for leaving WWE for a number of months, before revealing that Dr. Chris Amann failed to diagnose a staph infection that could have been fatal.

Punk is currently being sued by Amann for the comments that he made on Colt Cabana's podcast back in 2014, but it seems that Amann's negligence could have led to something much worse for Punk and it left him so ill that he could no longer compete for the company at that time. It is unknown as to whether or not he will ever wrestle for WWE again, but it's highly unlikely since the aforementioned lawsuit is still ongoing.